Characterization of Oxidized GaAs (001) Surfaces Using Temperature Programed Desorption and X-Ray Photoelectron Spectroscopy

Abstract

Temperature programed desorption (TPD) and X-ray photoelectron spectroscopy (XPS) were carried out on oxidized GaAs (001) surfaces in order to obtain insight into the durability of the oxide masks used in in situ selective-area processing. The TPD spectra comprised three successive desorption peaks showing the desorption of arsenic at 390°C, Ga2O at 475°C, and both Ga2O and arsenic above 500°C. XPS revealed the disappearance of As oxide and an increase of Ga oxide during the first desorption. The coexistence of two forms of Ga oxide, i.e., Ga2O and Ga2O3, is suggested, and a mechanism of oxide desorption is proposed.

Diffusion of In0.53Ga0.47As elements through hafnium oxide during post deposition annealing

“…15,17,28 For instance, Suri et al 28 established from ex-situ XPS that after depositing an HfO 2 film on native oxide-covered GaAs, no arsenic oxides are observed after a 400 C rapid thermal anneal for 20 s in a N 2 environment. Their observation is consistent with the well-established chemical reduction of As 2 O 3 on GaAs surfaces between the temperatures of 320 C-400 C, following the reaction: 29,30 As…”

Chemically selective adsorption of molecular oxygen on GaAs(100)c(2×8)

“…11 In thermal oxidation of GaAs, there has been controversy about whether Ga or As is oxidized first. 1,7,10,13,16,17,22,23,26 These studies find temperaturedependencies in the chemical selectivity that might be due both kinetic effects in the oxidation process 15 or different reconstructions. 4,6 Another important consideration in the comparison of the results of different studies is the coverage at which the measurements were made.…”

Effects of interfacial sulfidization and thermal annealing on the electrical properties of an atomic-layer-deposited Al2O3 gate dielectric on GaAs substrate

“…The critical temperature T c is defined as the temperature at which the reaction becomes thermodynamically favorable, i.e., where the Gibbs free energy of formation ͑⌬G f ͒ is less than zero; we obtained the values of T c from experimental results reported in the literatures. [21][22][23]34 We also calculated the value of ⌬G f for each of these stoichiometric equations. 32,33 If ⌬G f is greater than zero, the chemical reaction will not proceed; for example, the mechanisms associated with Ga 2 O formation are inhibited at room temperature, but an increase in temperature enhances the driving kinetics of the reaction.…”